auto-merge.yml

name: Auto Merge PR

on:
  pull_request_review:
    types: [submitted]

  pull_request:
    types: [labeled, unlabeled]

jobs:
  auto-merge:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout repository
        uses: actions/checkout@v2

      - name: Check Labels
        id: check-labels
        uses: actions/github-script@v6
        with:
          script: |
            const labels = context.payload.pull_request.labels.map(label => label.name);
            core.setOutput("no_auto_merge", labels.includes("no auto merge"));
            core.setOutput("auto_merge", labels.includes("auto approve"));
            core.setOutput("main_merge", labels.includes("main merge"));

      - name: Set Environment Variables
        run: |
          echo "NO_AUTO_MERGE=${{ steps.check-labels.outputs.no_auto_merge }}" >> $GITHUB_ENV
          echo "AUTO_MERGE=${{ steps.check-labels.outputs.auto_merge }}" >> $GITHUB_ENV
          echo "MAIN_MERGE=${{ steps.check-labels.outputs.main_merge }}" >> $GITHUB_ENV

      - name: Auto Approve if Auto Merge Label Exists
        if: env.AUTO_MERGE == 'true' && env.NO_AUTO_MERGE == 'false'
        uses: actions/github-script@v6
        with:
          script: |
            const token = process.env.ACCESS_TOKEN;
            await github.rest.pulls.createReview({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.payload.pull_request.number,
              event: 'APPROVE',
              body: '고생했다. 👍🏽',
              headers: {
                authorization: `token ${token}`
              }
            });
        env:
          ACCESS_TOKEN: ${{ secrets.ACCESS_TOKEN }}

      - name: Merge Pull Request on Review
        if: |
          github.event_name == 'pull_request_review' &&
          github.event.review.state == 'approved' &&
          env.NO_AUTO_MERGE == 'false'
        uses: actions/github-script@v6
        with:
          script: |
            const targetBranch = process.env.MAIN_MERGE === 'true' ? 'main' : 'dev';
            const prTitle = context.payload.pull_request.title;
            const prNumber = context.payload.pull_request.number;
            await github.rest.pulls.merge({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: prNumber,
              merge_method: 'squash',
              commit_title: `${prTitle} (#${prNumber})`,
              commit_message: 'Auto-merging PR',
              sha: context.payload.pull_request.head.sha,
              base: targetBranch
            });
        env:
          ACCESS_TOKEN: ${{ secrets.ACCESS_TOKEN }}

      - name: Merge Pull Request on Label
        if: |
          github.event_name == 'pull_request' &&
          github.event.action == 'labeled' &&
          env.NO_AUTO_MERGE == 'false'
        uses: actions/github-script@v6
        with:
          script: |
            const { data: reviews } = await github.rest.pulls.listReviews({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.payload.pull_request.number,
            });

            const approved = reviews.some(review => review.state === 'APPROVED');
            const prTitle = context.payload.pull_request.title;
            const prNumber = context.payload.pull_request.number;
            const targetBranch = process.env.MAIN_MERGE === 'true' ? 'main' : 'dev';

            if (approved) {
              await github.rest.pulls.merge({
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: prNumber,
                merge_method: 'squash',
                commit_title: `${prTitle} (#${prNumber})`,
                commit_message: 'Auto-merging PR',
                sha: context.payload.pull_request.head.sha,
                base: targetBranch
              });
            }
        env:
          ACCESS_TOKEN: ${{ secrets.ACCESS_TOKEN }}

      - name: Merge Pull Request on Unlabel
        if: |
          github.event_name == 'pull_request' &&
          github.event.action == 'unlabeled' &&
          github.event.label.name == 'no auto merge'
        uses: actions/github-script@v6
        with:
          script: |
            const { data: reviews } = await github.rest.pulls.listReviews({
              owner: context.repo.owner,
              repo: context.repo.repo,
              pull_number: context.payload.pull_request.number,
            });

            const approved = reviews.some(review => review.state === 'APPROVED');
            const labels = context.payload.pull_request.labels.map(label => label.name);
            const targetBranch = labels.includes("main merge") ? 'main' : 'dev';
            const prTitle = context.payload.pull_request.title;
            const prNumber = context.payload.pull_request.number;

            if (approved) {
              await github.rest.pulls.merge({
                owner: context.repo.owner,
                repo: context.repo.repo,
                pull_number: prNumber,
                merge_method: 'squash',
                commit_title: `${prTitle} (#${prNumber})`,
                commit_message: 'Auto-merging PR',
                sha: context.payload.pull_request.head.sha,
                base: targetBranch
              });
            }
        env:
          ACCESS_TOKEN: ${{ secrets.ACCESS_TOKEN }}